Top 20 NuGet XAML Packages

A rich library of helpers, services, and base classes for new and
existing Windows UWP apps to maximize awesomeness and minimize boilerplate garbage.
This library has a companion Visual Studio Extension called "Template 10 Template Pack".

Calcium is an application toolkit for creating UWP, Windows Phone, WPF, Silverlight and Xamarin applications. It provides much of what you need to rapidly build sophisticated yet maintainable applications.